Air-spring.



mmman J. G. FUNK.

AIR SPRING.

APPL'ICATION FILED DEC. 28, 1915 j Z 47 m Patented Oct. 3,1916

2 SHEETS-SHEET l.

HIP-

W/ViTNESS I. G. FUNK.-

AIR SPRING.

APPLICATION FILED DEC.28,1'915.

Patented Oct. 8, 1916.

2 SHEETS-SHEET 2 INVENTOR UNJKTED snares Parana?- JOHN G. FUNK, OF SWIS SVAIiE, PENNSYLVANIA, ASSIGNOR TO THE JOHN G. FUNK AIR SPRING COMPANY, OF PITTSBURGH, PENNSYLVANIA, A. GORPOIttATION OF DELAWARE.

Application filed December 28. 1915. Serial hi0. 6835b TouZZ 1/710212 it may] ("oil cm. Be it known that fl, Join G. FUNK, a citizen of the l mted States. and residing 1 11 the borough of Swissv alefin the county of Allegheny and Statb "of lemisylvania, have invented or discoveredmew and useful Im proyeinents in Air-Springs, of which the V A represents a, portion of the vehicle following is a specification. l

My lllVQlltlOlfhCOllSlStS ofa new and improved air-spring or cushion device intended for use either as a substitute for or in con-1 ncction with the usual resilient metallic springs of a vehic e, such as an automobile; four of my air-f 'n'ings being usually provided for each vehicle, twofor each axle.

Generally speaking, my air-spring comprises a pairof telescopicelements, such as cylinders, one element being connected to one portion of the vehicle, such as the frame, while the other element is connected to another portion of the vehicle, such as a leaf spring: an air-pumping chamber mounted on one of the elements and provided with a valved opening to atmosphere, and a piston, provided with a valved opening into the in teriorof the air-spring proper, working in said air-pumpingch amber and connected by means of av spring with the other element. An adjustable automatic relief valve is provided so that the internal pressure of the airspring maybe maintained at that required to cushion the load.

New and improved means are provided for mounting the air-spring in position whereby the torsional and other thrusts, set up by the travel of the vehicle, are prevented from racking and damaging the alrspring and impairing its eflicient operation.

Other novel features of construction and arrangement of parts will appearfrom the following description.

In the accompanying drawings, which are merely intended to" illustrate the principles of my invention but not to limit the scope of the same to the construction shown, Figure 1 is a; vertical section of my improved air spring interposed between the frame and the lea fspring of-a vehicle; Fig. 2 is a sectional view-of the same taken along the line 11-11 in Fig. 1 ;-Fig. 3 is a similar view along the .line' III III in Fig. 1; F' I' are abroken elevation of the lower end o tliefairspring,

the ipiston rod and its connection "with the leaf-springof the vehicle-beingshown 1n Specification of Letters Patent.

fram aand B one of the leaf AIR-SPRING Patented @ct. 3, 9156.

section along the line IV-IVin Fig. 1 and i Fig. 5 is a broken elevation of the lower end of the. piston rod and its connections show-\ ing the former swung out of its normal relation to the leaf spring. 3i The following is a detailed description of the drawings. i

a springs. I C ar d @Drepresent a pair ofabutting and ahned cylindrical sleeves coupled together by means of the internally threaded Ting E which is bolted or'otherwise securedto the frame A, If desired, the sleeves C and D maybe integral but for convenience in assembling, I prefer the two sleeves connected together ;as shown.

F is a cap providedwith an annular flange 1 both externally and internally threaded, as shown. The upper or outer end of the sleeve C. is internally threaded and screwed on the external threads of said flange. Y

-G is a cylinder jwhose upper end isexternally threaded and screwed'into the internal threads of the flange l. The cylinder G thus extends within the sleeve C and is spaced within the same the thickness of the flange l.

H is the outer cylinder whose open or upper end reciprocates in the annular space tetween the said inner cylinder G and the sleeve C, packing rings 2 beingprovided on the exteriors of both cylinders to prevent the escape of pressure from-the interior of the air-spring. The head or outer end of I the cylinder H is solid except for a central threaded aperture 8.

I is a piston rod which extends inwardly "through thehead of cylinder H and is prorodI and the cylinder H are rlgidly connected and move in unison. The piston I is hollow and within the cylinder H is bored an open top air-pumping chamout to for beret in" whi'ch moves a piston J provided with anmpWard ly'openingairvalve 5. Said valve is preferably a ball valve held nor- '65 red is enlarged at right angles to the .mally seated in the upper end of the air passage 6 by means of a spring actuated plunger 7 mounted in the nipple 8 which is held seated in the axial bore, of the piston J by means of a split spring ring 9 seated in an annular groove 10 in said bore. vertical air passages cut in theperimeter of said nipple 8 for the upward escape of air from the air-pumping chamber 4 when the valve 5 is open. The piston is provided with suitable paeking'rings as shown.

K a relatively heavy helical spring whose lower end is mounted in an annular shoulder 12 on the piston J and whose upa per end is seated against an annular flange 13 onya bushing 14, which bushing depends through an axial hole '15 in the cap. F. The outer end" of said bushing is externally threaded to receive the. clamping nut 16 whereby said bushing is rigidly locked in place with the "flangefllir drawn snugly against the inner face of the cap F.

17 is a dome shaped cage mountedon the external threaded end of bushing 14 andprovided with ports 18 in its wall.

.19 is a puppet valve, hav ng its lower stem squared and depending in the bushing 14,

normally held inplace to'close the bore of said bushing by means of a helical spring 19 and bearing at its ends against said valve 20 coiled aboutthe upper stem of said valve -and against the cage 17, as shown. It is evident that by tightening or loosening the cage 17 on the bushing 14, the tension of the spring 20may be regulated to permit the valve 19 to open automatically atany pre- 7 determined pressure in the air spring to relieve the excess pressure.

The lower or lesser bore-2'1 of the piston rod I is countersunk at its inner end to form a seat 22.to receive the flanged end of a bushing 23 which fits in the upperpor- .tion of said bore 21. The lower end of the bore f b g hi'ng 23 is contracted to form an groove 29 in said bushing. v

27 represents 'vertlcal grooves; in the perimeter of the nipple 27 to permitair to pass upwardly into the air-pumping chamber 4 when the valve 25 is open.

L is a cross head screwed in place in the.

- interior. of sleeve D and provided with a stufiingbox through which the-piston rod I extends. It is evident that the piston rod and the outer cylinder" are thus maintained at alltimes in perfect alinement with the inner cylinder andthe' outer sleeves and that no pressure can escape through the open end of the sleeve'D. The bore 21 of the piston 11 are block M.

of the bolt.

frame" A to provide a socket to receive the convex head of a block M. and at either side the wall of saidipiston rod is extended downwardly or outwardly to, form a convexly curved bearing surface 30 which seats in a concaved bearing surface. 31 'on' the 32 is a heavy through registering holes in the walls of the piston rod I and the block M whereby said boltor rivet which ektends elements are attached together in such a manner as to permit a rocking, pivotal.

movement between-them. The under or outer face of the block M is provided with a slide way 33 of dovetail cross section extending transversely of said block at right angles to its plane ofmovement. From said slideway 33 two diverging ports 34 communicate with grooves 35 in the walls of the piston rod 1 extending to the bore 21 of said piston rod, thereby assuring continuous communication between the piston rod bore and the slideway33 whatever the relative positions of the piston rod I and the block M may be.

N, is a hanger block provided at its topwith a dovetail projection 36 which seats and slides in slideway'33.

37 are antifriction balls seated in race-' ways out in the abutting faces of the blocks M and N to facilitate the sliding movement of the block .N in relation to. the block M. I

The block N is provided with a transverse bore 38 which, is cut away or exposed for less than half its perimeter by means of an aperture 39 extending into the said bore from the front of the-block N.

'40 is the usualeye on the end ofthe' leaf spring B which is slipped sidewise into the bore 38, the leaf spring extending out through the aperture 39. Large washers 41 are now applied to close the ends of the bore 38 and the bolt 42 inserted through said washers and the eye 40 of the leaf spring, and the nut 43 .screwed tightly on the end thus pivotallyheld in the bore 38. Pref- It is evident 'that' the eye iserably a. bushing 44 is interposed between the eye 40 and the bolt 42 to give freer pivotal movement to the eye.

' The front wallof the sleeve D is cut away for a distance from the bottom-to form a slot 45 to give clearance for the protruding leaf spring B as the air spring contracts.-

'46 is-an' air port extending from the front of the hanger block 'N through the projection 36 and cutthrough to the top of said projection except .at the front to maintain constant communication to atmosphere for the ports 34 in the block M. Thus atall times air is free to enter the bore 21 of the piston rod'I. 47 's a screw plugged openingin the cap F by means of which compressed air may be introduced into the air spring to induce upon the air-sp ring.

compressible liquid, such as the oil a up to substantially the top of the chamber 4. The operation of my improved air-spring is as follows: Assuming the proper initial pressure within the air-spring, the relief valve 19 is adjusted to automatically open at the proper cylinder .pressure. Thus a heavily loaded vehicle will require a higher pressure in the air-springs to balance or cushion the load than will a lightly loaded vehicle, so that the excess pressure relief valve 19 should be adjusted to operate automatically whenever the internal pressure of the airspring rises above that dictated by the load The vehicle is now put in motion, causing the air-spring to alternately contract and expand through the telescopic action of the-cylinders G and H. The telescopic action between the said cylin ders causes a similar reciprocation of the piston J in the air-pumping chamber at. The descent of. the piston J in said chamber holds the valve25 closed while the compres sion of the air in said chamber below the descending piston forces open the valve 5, permitting the air, to rush upwardly through the passeges ll'into the interior of the cyl incler G above the liquid on. On the other hand, the return-or upward movement of the piston J in the chamber 4 closes the valve 5' and sucks open the valve 25, causing air to be drawn up through the piston rod into the chamber 4, below the. piston J, thus refilling said chamber.

It is evident that the continued recipro cation of the piston, as the, air-spring alternately expands and contracts, will raise the internal pressure of the until such pressure, exerted on the upper side of the ball valve 5, is suiiicient to hold said valve closed by balancing the efiect of the load upon theair-spring. Thus no more air will be pumped into the interior of the airspring unless-the internal pressure of the same is lowered by leakage or the load is increased. In either case, the valve 5 will beforced open and the internal pressure of the air-spring will be restored "or increased,

as the case may be, to the proper degree tobalance the load. Thus the proper balancing or cushioning pressure will be automatically established and maintained.

In case a sudden jolt or abnormal reciprocation of the telescopic parts of the airspring unduly raises the internal pressure, the relief valve 19 will momentaril to relieve said excess pressure an close,

when said relief is accomplished, withoutlowering the pressure below the predeter.

mined point.

The resillent connection between the'pisopen normal contractionof the air-spring causes the piston to descend-to the bottom of th e chamber 4, nosudden jar or jolt results.

As the air-springexpands, the pressure. ex-

erted against the upperface of the piston and the resiliency of the spring K will cause the piston to lag slightly while the descent of the piston incompressing'the air in cham her 4 will be accelerated by the pressure above the piston, causing the piston to travel more rapidly than the cylinder Gr thus augmenting the injection of air from the pumping chamber l into the cushion chamber proper. The liquid a tightly seals the" sliding joints of the air-spring against loss of internal pressure and lubricates the moving parts. i

It is evident that the telescopic partsof the air-spring are held in proper alinement by means of the sleeves C and D and the crosshead L, so that the reciprocal action is protected from impairment and the sliding joints maintain their efliciency. The method of attaching the cylinder H to the vehicle, such as the leaf-spring B, issuch that all irregularities of movement which occur between the portions of the vehicle, such as the frame and the axle or leaf spring, are taken up and assumed without the telescoping elements of the air-spring. Thus the pivotal connectionbetween the hanger block N and the leaf-spring combined with the sliding movement of the block N in the block ll to expand and contract freely with the mo- 1. In an air-sprmg, a pair of telescopmg elements forming a cushion chamber, a pumping chamber within said cushion chamber and mounted on and moving with one of said telescopic elements, an inwardly opening valve connecting said pumping chamber to atmosphere, a pumping piston working in said pumping chamber and provided with 'a valve connecting said chambers and a resilient mechanical connection between the second telescopic element and said pumping piston, for the purpose de-' scribed.

2. In an a1r-spr1ng,'a pair of telescoping elements forming a cushion chamber, a pumping. chamber within sa1d CUShlOIlChEHl: ber mounted on and moving with one of said telescopic elements, an inwardly op'ere mg valve connect ng sa1d pump1ng ehamher with atmosphere, a pumping piston enables the leaf-spring tion of the vehicle, while the pivotal conworking in saidpumping chamber, a valve'f in said piston connecting said chambers," and a helical spring connecting said pump--v ing piston with the other telescopic element whereby the same move in substantial unison, for the purpose described.

' 3, In an air-spring, a pair of telescoping elements forming a cushion chamber, av

pumping 'chamber within said cushion chamber'monnted on and moving with one of said 'telescopicelements and having a Qvalved inlet port communicating with atmosphere, and a pumping piston working in sald pumping chamber and having a res1l- 1 ient mechanical connection with the other ingichainber, for the purpose described.

ningconnection' between said member and said leafspring.

" 4. The combination with a vehicle and a telescopic cushion device to be interposed I 20 between two portionsof the vehicle and having one of itselements attached to one of said portions, of a member pivotall'y at-- tached to the other element of said cushion device and swinging a vertical plane 25 transverse to the line of travel of the vehicle', "anda sliding connection between said member and the other portion of said vehicle, the sliding motion beingin the line of travel of the vehicle.

5. The combination with a load platform of -a"vehicle, of a leaf-spring carried by the running gear, a telescopic; cushion device one element of which is secured to said load platform,- armember pivoted to the other elemeiitof said cushion device, and ,a slid- 6. 'The combination with the load plat form o'fi a vehi Ie, of a leaf spring carried by the running gear, a telesco'pic cushion device one element of which .is secured to said load platform, a member pivoted to'the other element of said cushion device and adapted to swing transversely to, said leaf,

spring, and a sliding pivotal connection between said member andsaid leaf sprin 7. The combination with the load p atform of a vehicle, of a leaf spring carried by the running gear, a telescopic cushion device one element of which is secured to saidload platform, a member pivoted to the other element of said cushion device and adapted to swing transversely to said leal spring, said member being'provided with a slideway transverse to the direction of its pivotal swing, and a block mounted on said leaf spring and traveling along said slideway.

8. In combination with the piston rod of atelescopic cushion device, a mounting for said piston rod consisting of a member pivotally connected to the outer end of said rod and a slide mounted in said member transverse to the pivotal swing of the latter.

9. In combination with the piston rod of a telescopic cushion device and the spring of a vehicle, a mounting for said piston rod comprising a member pivoted to the outer end of said rod transversely to the spring, and a slide mounted in said member and attached to said spring.

10. In combination with the piston rod of a telescopic air spring, a mounting for said piston rod for attaching the same to a vehicle comprising a membervpivoted to the outer end of said rod, and a slide mounted to a portion of the vehicle, said rod, member and slide being provided with a continuous in said member and adapted to be attached 

